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MODBUS_WRITE_AND_REA(3)	       libmodbus Manual	       MODBUS_WRITE_AND_REA(3)

NAME
       modbus_write_and_read_registers - write and read	many registers in a
       single transaction

SYNOPSIS
       int modbus_write_and_read_registers(modbus_t *ctx, int write_addr, int
       write_nb, const uint16_t	*src, int read_addr, int read_nb, const
       uint16_t	*dest);

DESCRIPTION
       The modbus_write_and_read_registers() function shall write the content
       of the write_nb holding registers from the array	src to the address
       write_addr of the remote	device then shall read the content of the
       read_nb holding registers to the	address	read_addr of the remote
       device. The result of reading is	stored in dest array as	word values
       (16 bits).

       You must	take care to allocate enough memory to store the results in
       dest (at	least nb * sizeof(uint16_t)).

       The function uses the Modbus function code 0x17 (write/read registers).

RETURN VALUE
       The function shall return the number of read registers if successful.
       Otherwise it shall return -1 and	set errno.

ERRORS
       EMBMDATA
	   Too many registers requested, Too many registers to write

SEE ALSO
       modbus_read_registers(3)	modbus_write_register(3)
       modbus_write_registers(3)

AUTHORS
       The libmodbus documentation was written by StA(C)phane Raimbault
       <stephane.raimbault@gmail.com>

libmodbus v3.1.6		  03/01/2021	       MODBUS_WRITE_AND_REA(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | SEE ALSO | AUTHORS

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